diff options
Diffstat (limited to 'build2/variable')
| -rw-r--r-- | build2/variable | 33 |
1 files changed, 25 insertions, 8 deletions
diff --git a/build2/variable b/build2/variable index 690c45d..ea1912a 100644 --- a/build2/variable +++ b/build2/variable @@ -233,13 +233,7 @@ namespace build2 // specialization below). Types that don't fit will have to be handled // with an extra dynamic allocation. // - // std::max() is not constexpr on GCC 4.9. - // - static constexpr size_t size_ = - sizeof (names) > sizeof (target_triplet) - ? sizeof (names) - : sizeof (target_triplet); - + static constexpr size_t size_ = sizeof (name_pair); std::aligned_storage<size_>::type data_; // Make sure we have sufficient storage for untyped values. @@ -653,7 +647,7 @@ namespace build2 static name convert (name&&, name*); static void assign (value&, name&&); static name reverse (const name& x) {return x;} - static int compare (const name&, const name&); + static int compare (const name& l, const name& r) {return l.compare (r);} static bool empty (const name& x) {return x.empty ();} static const bool empty_value = true; @@ -661,6 +655,29 @@ namespace build2 static const build2::value_type value_type; }; + // name_pair + // + // An empty first or second half of a pair is treated as unspecified (this + // way it can be usage-specific whether a single value is first or second + // half of a pair). If both are empty then this is an empty value (and not a + // pair of two empties). + // + template <> + struct value_traits<name_pair> + { + static_assert (sizeof (name_pair) <= value::size_, "insufficient space"); + + static name_pair convert (name&&, name*); + static void assign (value&, name_pair&&); + static int compare (const name_pair&, const name_pair&); + static bool empty (const name_pair& x) { + return x.first.empty () && x.second.empty ();} + + static const bool empty_value = true; + static const char* const type_name; + static const build2::value_type value_type; + }; + // process_path // // Note that instances that we store always have non-empty recall and |